1. Technical Field
Various embodiments of the present invention relate to a memory system, and more specifically, to a memory system including a memory device and a controller.
2. Related Art
A flash memory device may store two or more data bits per cell in order to store a larger amount of information in a limited storage space. As the number of data bits stored in a memory cell is increased, the number of threshold voltage distributions is increased and the distance between the threshold voltage distributions is decreased. Accordingly, adjacent threshold voltage distributions may overlap each other.
As adjacent threshold voltage distributions overlap each other, the data read from the cell may include a large number of error bits (several to several tens of error bits). Accordingly, there is an imperative need for technology to efficiently detect and correct errors of data read in the flash memory device storing multi-bit data.